Paul Gainey - 26-Jul-2007
- Work has started on installing new fish
passes at Blachford Lake to allow passage
of salmon and sea trout past two weirs under
a wide range of flows.
The fish passes are expected to be completed
in September ready for the next migration
season.
Blachford Lake provides the main barrier
to salmon migration on the River Yealm, preventing
access to the fish spawning grounds on Dartmoor.
This joint initiative is supported by other
partner agencies including Action for Wildlife
(AFW), Westcountry Rivers Trust (WRT) and
the Yealm River Association (YRA).
A decline in salmon numbers nationally, as
well as in Dartmoor’s rivers has caused concern
for some years. Work to improve spawning and
freshwater habitats have been made by the
Environment Agency and its partner organisations
within numerous river catchments.
‘We have all done a lot of work to improve
the river Yealm’s wildlife habitats but the
fish are isolated in parts of the river because
there is this major barrier at Blachford.
We want to change this by installing a fish
pass to allow the fish to move freely,’ said
Lesley Newport.
The work, which is being carried out by the
Environment Agency’s workforce, comprises
the removal of the existing seven metre long
stone upper weir and replacement with a pool
and traverse fish pass, with minimal alterations
to the lower weir to improve fish passage.
Like many salmon rivers, the River Yealm
has a ‘Salmon Action Plan’ that pinpoints
the main threats to local salmon stocks and
helps the Environment Agency and its partners
decide how best to boost fish numbers.
The plan includes a conservation limit. This
is a target for the number of salmon eggs
needed to ensure enough young salmon survive
in the river to sustain a healthy population.
At present, the River Yealm is failing to
reach its salmon conservation limit.
Improving the future for salmon is not a
straightforward business. Migratory fish species
travel between the sea and freshwater in order
to complete their lifecycles. Some, like salmon
and sea trout are returning to their native
streams to breed, while others, such as eels,
come to our rivers to grow before returning
to the sea to spawn.
‘Thankfully these fish are benefiting from
cleaner water in our rivers, but they still
face major problems. Man made barriers to
migration, such as weirs and dams can block
fish migrating to their spawning grounds and
back out to sea, thereby severely restricting
fish numbers,’ added Lesley Newport
At least 15km of spawning grounds will be
opened up to salmon spawning by the new fish
passes. Once built, the Environment Agency
will monitor the biodiversity improvements
and fish populations, using cameras in the
fish pass and electric fishing surveys.
Russell Weston, of the Yealm River Association,
said:’We are delighted that the partners have
been able to find the funding for this vital
improvement and look forward to it being completed.’
